The purpose of this study is to develop an engineering and operational understanding of CAES performance for a depleted natural gas reservoir by evaluation of relative permeability effects of air, water and natural gas in depleted natural gas reservoirs as a reservoir is initially depleted, an air bubble is created, and as air is initially cycled. The composition of produced gases will be evaluated as the three phase flow of methane, nitrogen and brine are modeled. The effects of a methane gas phase on the relative permeability of air in a formation are investigated and the composition of the produced fluid, which consists primarily of the amount of natural gas in the produced air are determined. Simulations of compressed air energy storage (CAES) in depleted natural gas reservoirs were carried out to assess the effect of formation permeability on the design of a simple CAES system. The injection of N2 (as a proxy to air), and the extraction of the resulting gas mixture in a depleted natural gas reservoir were modeled using the TOUGH2 reservoir simulator with the EOS7c equation of state. The optimal borehole spacing was determined as a function of the formation scale intrinsic permeability. Natural gas reservoir …

None

None

None

None

None

None

None

None

None

Proceedings of the House of Representatives of Texas for the sixth day of the First Called session of the 83rd Legislature documenting legislation, reports, discussions, votes, and points-of-order.

None

None

Journal containing articles, notes, book reviews, and other analyses of law and legal cases. This issue covers the symposium over constitutional foundations.

This study examines how grid-level electricity storage may benet the operations of NV Energy in 2020, and assesses whether those benets justify the cost of the storage system. In order to determine how grid-level storage might impact NV Energy, an hourly production cost model of the Nevada Balancing Authority (\BA") as projected for 2020 was built and used for the study. Storage facilities were found to add value primarily by providing reserve. Value provided by the provision of time-of-day shifting was found to be limited. If regulating reserve from storage is valued the same as that from slower ramp rate resources, then it appears that a reciprocating engine generator could provide additional capacity at a lower cost than a pumped storage hydro plant or large storage capacity battery system. In addition, a 25-MW battery storage facility would need to cost $650/kW or less in order to produce a positive Net Present Value (NPV). However, if regulating reserve provided by storage is considered to be more useful to the grid than that from slower ramp rate resources, then a grid-level storage facility may have a positive NPV even at today's storage system capital costs. The value of having storage provide services …

Semi-weekly newspaper from Copperas Cove, Texas that includes local, state and national news along with advertising.

Semi-weekly newspaper from Copperas Cove, Texas that includes local, state and national news along with advertising.

This study examines how grid-level electricity storage may benefit the operations of NV Energy, and assesses whether those benefits are likely to justify the cost of the storage system. To determine the impact of grid-level storage, an hourly production cost model of the Nevada Balancing Authority (%22BA%22) as projected for 2020 was created. Storage was found to add value primarily through the provision of regulating reserve. Certain storage resources were found likely to be cost-effective even without considering their capacity value, as long as their effectiveness in providing regulating reserve was taken into account. Giving fast resources credit for their ability to provide regulating reserve is reasonable, given the adoption of FERC Order 755 (%22Pay-for-performance%22). Using a traditional five-minute test to determine how much a resource can contribute to regulating reserve does not adequately value fast-ramping resources, as the regulating reserve these resources can provide is constrained by their installed capacity. While an approximation was made to consider the additional value provided by a fast-ramping resource, a more precise valuation requires an alternate regulating reserve methodology. Developing and modeling a new regulating reserve methodology for NV Energy was beyond the scope of this study, as was assessing the incremental value …

Weekly newspaper from Cooper, Texas that includes local, state, and national news along with advertising.

Weekly newspaper from Cooper, Texas that includes local, state, and national news along with advertising.

Weekly newspaper from Hondo, Texas that includes local, state, and national news along with advertising.

Sheet from the Texas Commission on Environmental Quality (TCEQ) listing contact information for each of the 16 Texas regional offices as well as the watermasters. The back includes a map showing the counties included in each of the corresponding regions.

Sheet from the Texas Commission on Environmental Quality (TCEQ) listing contact information for each of the 16 Texas regional offices as well as the watermasters. The back includes a map showing the counties included in each of the corresponding regions.

Sheet from the Texas Commission on Environmental Quality (TCEQ) listing contact information for each of the 16 Texas regional offices as well as the watermasters. The back includes a map showing the counties included in each of the corresponding regions.